October 2009

This event on the 14th October (Figure A) was part of large scale European dynamical disturbance which affected much of the troposphere and lower stratosphere. It was characterised by an intrusion of low ozone air over Lerwick. Examination of the Northern Hemisphere thickness (Figure B) reveals that this event was part of a warm tongue of tropospheric air pushing in from the south over Lerwick. The relatively warm tropospheric air lifted the tropopause height and also advected low ozone from the South over Lerwick. This pool of low ozone air was then advected westwards over Scandinavia and Russia.

Figure A: Ozone anomaly maps during the peak of the ozone event on 14th October.

This event on the 14th October (Figure A) was part of large scale European dynamical disturbance which affected much of the troposphere and lower stratosphere. It was characterised by an intrusion of low ozone air over Lerwick. Examination of the Northern Hemisphere thickness (Figure B) reveals that this event was part of a warm tongue of tropospheric air pushing in from the south over Lerwick. The relatively warm tropospheric air lifted the tropopause height and also advected low ozone from the South over Lerwick. This pool of low ozone air was then advected westwards over Scandinavia and Russia.

Figure A: Ozone anomaly maps during the peak of the ozone event on 14th October.